CN112673442A

CN112673442A - Arc extinguishing circuit and device

Info

Publication number: CN112673442A
Application number: CN201980044837.7A
Authority: CN
Inventors: 郭桥石
Original assignee: Individual
Current assignee: Guangzhou Kingser Electronics Co ltd
Priority date: 2018-09-19
Filing date: 2019-09-18
Publication date: 2021-04-16
Anticipated expiration: 2039-09-18
Also published as: WO2020057551A1; US12014893B2; AU2019341286A1; CN112673442B; AU2019341286B2; US20210375561A1

Abstract

An arc extinguishing circuit and device, especially suitable for the arc extinguishing circuit and device to mechanical switch arc extinguishing, the mechanical switch (K) that needs arc extinguishing connects in series with load (RL) and makes up the first series circuit, it includes the first switch (S1), the first charging unit (U1), the first electric capacity (C1); the first power supply charges a first capacitor (C1) through a first charging unit (U1), and the second power supply supplies power to a load (RL) through a first switch (S1) and a first capacitor (C1) in the breaking process of a mechanical switch (K); the first charging unit (U1) is a first element, or a second switch, or is composed of the first element and the second switch in series. The arc extinguishing circuit and the arc extinguishing device have the advantages of high capacity utilization rate of the capacitor and simple circuit.

Description

Arc extinguishing circuit and device

Technical Field

The invention relates to an arc extinguishing circuit and device, in particular to an arc extinguishing circuit and device suitable for arc extinguishing of mechanical switches such as contactors (relays) and the like, and can also be used for arc extinguishing of other breakpoints (such as fusing of a fuse link, breakpoints between a plug and a socket and wire breakpoints).

Background

At present, in electric control systems of new energy automobiles, rail transit, ships, automation control and the like, mechanical switches such as contactors (relays) and the like are generally used for carrying out frequent connection and disconnection control on loads, and due to the fact that mechanical switches have disconnection electric arcs, particularly direct currents, and due to the fact that zero points are not arranged, the disconnection electric arcs are larger, the defect that the electrical service life of the mechanical switches is short is overcome, and the electrical service life of the mechanical switches is greatly shortened along with the increase of the disconnection voltage and the disconnection current of the mechanical switches.

Disclosure of Invention

The invention aims to solve the problem of short electrical service life of a mechanical switch in the existing electric control system, and provides an arc extinguishing circuit and device which are high in capacitance utilization rate, simple in circuit, good in arc extinguishing effect and high in reliability.

The purpose of the invention is achieved by the following technical scheme:

an arc extinguishing circuit is characterized in that a mechanical switch required to extinguish arc is connected with a load in series to form a first series circuit, and the first series circuit comprises a first switch, a first charging unit and a first capacitor;

the first power supply charges the first capacitor through the first charging unit, and the second power supply supplies power to the load through the first switch and the first capacitor in the breaking process of the mechanical switch;

the first charging unit is a first element, or a second switch, or is formed by connecting the first element and the second switch in series.

The working principle is as follows: before the mechanical switch is switched off, the first capacitor is charged by the first power supply through the first charging unit, and in the switching-off process of the mechanical switch, the second power supply supplies power to the load through the first switch and the first capacitor (namely, the voltage of the second power supply and the voltage of the first capacitor are superposed and supplied to the load), so that the aim of arc extinction of the mechanical switch is fulfilled.

The invention has the advantages of reasonable design, high utilization rate of capacitance capacity, simple circuit, good arc extinguishing effect and high reliability.

Drawings

Fig. 1 is a schematic circuit diagram of an embodiment of an arc extinguishing circuit and an arc extinguishing device according to the present invention.

Fig. 2 is a schematic diagram of an opto-coupler voltage detection unit circuit of the arc extinguishing circuit of the present invention.

FIG. 3 is one of two schematic circuit diagrams of an arc extinguishing circuit and an arc extinguishing device according to an embodiment of the present invention.

Fig. 4 is a second schematic circuit diagram of the arc extinguishing circuit and the arc extinguishing device according to the second embodiment of the present invention.

Fig. 5 is one of three circuit schematic diagrams of an embodiment of an arc extinguishing circuit of the invention.

Fig. 6 is a second schematic circuit diagram of an embodiment of an arc extinguishing circuit of the invention and a third schematic circuit diagram of an embodiment of an arc extinguishing device of the invention.

Fig. 7 is a third schematic circuit diagram of an embodiment of an arc extinguishing circuit of the invention and a fourth schematic circuit diagram of an embodiment of an arc extinguishing device of the invention.

Fig. 8 is a ninth switching circuit of the arc extinguishing circuit of the present invention.

Fig. 9 is a schematic diagram of a fourth switch and diode series circuit of the arc extinguishing circuit of the present invention.

Fig. 10 is a fifth schematic view of an arc extinguishing device according to an embodiment of the present invention.

Fig. 11 is one of six schematic circuit diagrams of an embodiment of an arc extinguishing device according to the present invention.

Fig. 12 is a second schematic diagram of a six-circuit embodiment of an arc extinguishing device according to the present invention.

Fig. 13 is a third schematic diagram of six circuits of an embodiment of an arc extinguishing device according to the present invention.

Fig. 14 is a fourth schematic diagram of a six-circuit embodiment of the arc extinguishing device of the present invention.

Fig. 15 is a schematic diagram of a sixth circuit of an embodiment of an arc extinguishing device according to the present invention.

Fig. 16 is a schematic diagram of six circuits of an embodiment of the arc extinguishing device of the present invention.

Fig. 17 is a seventh schematic view of an arc extinguishing device according to an embodiment of the present invention.

Detailed Description

Fig. 1 shows a first embodiment of an arc extinguishing circuit and an arc extinguishing device according to the present invention:

an arc extinguishing circuit, a mechanical switch K and a load RL which need to extinguish arc are connected in series to form a first series circuit, and the first series circuit comprises a first switch S1, a first capacitor C1 and a first charging unit U1 (a first element R1 and a second switch S2 are connected in series); the mechanical switch K is closed, a first power supply connected in a first series circuit (provided by a power supply connected to two ends of the load RL, namely the output end of the mechanical switch K, and also provided by another power supply) charges a first capacitor C1 through a first charging unit U1 (reverse pre-charging), namely a series circuit consisting of a first capacitor C1 and a first charging unit U1 is connected with the load RL in parallel, during the breaking process of the mechanical switch K, a second power supply (provided by the power supply connected in the first series circuit, provided by the input end of the mechanical switch K, and also provided by another power supply) supplies power to the load RL through a first switch S1 and a first capacitor C1 (namely the series circuit consisting of a first switch S1 and a first capacitor C1 is connected with the mechanical switch K in parallel), namely the power supply at the input end of the mechanical switch K charges a first capacitor C1 in a forward direction through a first switch S1 (the voltage of the second power supply is superposed with the voltage of the first capacitor C1), the purpose of arc extinction of the mechanical switch K is achieved, after the mechanical switch K is disconnected, the first capacitor C1 is fully charged in the forward direction, then the second switch S2 is conducted, and the first capacitor C1 is discharged through the first element R1, the second switch S2 and the load RL (or the load RL is connected with a diode in parallel to be discharged in a bypass mode), so that the next working process is prepared. Note: the first element R1 and the second switch S2 of the first charging unit U1 can be selected from one to another.

The embodiment has the characteristics of simple circuit and no impact current when being electrified.

An arc quenching device comprising the arc quenching circuit as described above:

the control circuit also comprises a control unit U, control signals of the first switch S1 and the second switch S2 are provided by the control unit U, voltage signals at two ends of the mechanical switch K are transmitted to the control unit U (signals of an auxiliary switch of the mechanical switch K can also be transmitted to the control unit U), the control unit U is used for detecting the disconnection of the mechanical switch K, the control unit U is used for detecting the charging voltage (the voltage of a C endpoint) of the first capacitor C1, the voltage at two ends of the first capacitor C1 can also be provided to the control unit U (the optocoupler voltage detection unit can be internally arranged in the control unit U) by adopting an optocoupler voltage detection unit (shown in figure 2), and the optocoupler voltage detection unit is formed by connecting a diode DA, a voltage stabilizer ZA (which can adopt the same device such as a voltage stabilizing diode and a voltage sensitive diode), a photocoupler OPT 1; in the arc extinguishing process, when the control unit U detects that the arc extinguishing fails (i.e., the first switch S1 is turned off, and the second power supply cannot charge the first capacitor C1 in the forward direction), the control unit U controls the second switch S2 to be turned on, and charges the first capacitor C1 in the reverse direction quickly, and then performs the second arc extinguishing.

The second embodiment of the arc extinguishing circuit and the arc extinguishing device of the invention is shown in fig. 3 and 4:

an arc extinguishing circuit is characterized in that a mechanical switch K required to extinguish arc is connected with a load RL in series to form a first series circuit, and the first series circuit comprises a first switch S1, a second switch S2, a third switch S3, a fourth switch S4, a first capacitor C1, a first element R1, a first diode D1 (used for discharging the first capacitor C1), a second diode D2 and a second element R2; a first element R1 and a second switch S2 are connected in series to form a first charging unit for charging a first capacitor C1, a second element R2 (optional), a third switch S3, a first capacitor C1, a first element R1 (optional) and a second switch S2 form a third series circuit, a first power supply (provided by power connected with two ends of the first series circuit, provided by an input end of a mechanical switch K, and also provided by another power supply) connected with the first series circuit is connected with the third series circuit, and the third series circuit is used for charging (reversely pre-charging) the first capacitor C1; the first switch S1, the first capacitor C1 and the fourth switch S4 form a second series circuit, and in the disjunction process of the mechanical switch K, a second power supply (provided by power supplies connected with two ends of the first series circuit, provided by the input end of the mechanical switch K, or provided by another power supply) supplies power to the load RL through the second series circuit (the voltage of the second power supply is superposed with the voltage of the first capacitor C1), so that the aim of arc extinction of the mechanical switch K is fulfilled; the technical scheme that a voltage signal (which can be a common terminal to ground voltage signal; or a voltage between the common terminal to the sixth element R6 and the power supply) at the common terminal of the sixth element R6, the eighth switch S8, the eighth switch S8 and the fourth switch S4 is transmitted to the control unit U can be used for detecting the working states (off, on, breakdown) of the fourth switch S4 and the third switch S3.

After the mechanical switch K is disconnected, the first capacitor C1 is fully charged in the forward direction, the third switch S3 is turned on, the first capacitor C1 is discharged through the first diode D1, the second element R2 and the third switch S3 (note: the circuit may also be changed into a circuit in which one end of the first diode D1 is grounded, the other end of the first diode D1 is connected with the first capacitor C1, that is, the a end point is connected, and the first capacitor C1 is discharged through the first element R1, the second switch S2 and the first diode D1), so as to prepare for the next working process; the second element R2 (optional), the third switch S3, and the fourth switch S4 form a fourth series circuit, and before or during the closing of the mechanical switch K, the second power supply supplies power to the load RL through the fourth series circuit, so as to close the mechanical switch K for arc extinction, or to pre-charge the load RL (such as a capacitive load, a motor controller, a dc converter, etc.), so that the current impact of the capacitive load on the mechanical switch K can be effectively overcome, and: during the closing process of the mechanical switch K, if the first switch S1 is also turned on, the closing bounce arc extinguishing effect of the mechanical switch K is better because the third switch S3 provides a discharging loop for the first capacitor C1, while the third switch S3 keeps supplying power to the load RL, and the first capacitor C1 also supplies power to the load RL;

the second diode D2 is used for grounding the first capacitor C1, so that the control unit U can sample the voltage at the a-terminal conveniently, and can select the voltage as required (when the second switch S2 is provided with a built-in diode, the diode can be omitted); when the first power is not supplied by the power connected to the first series circuit and is inputted from the terminal a, the second element R2 and the third switch S3 are selected as required.

FIG. 4 is a fifth series circuit formed by adding a sixth switch S6, a third capacitor C3, a fifth switch S5 (preferably a diode; or a controllable switch provided by a control unit with a control signal, such as a unidirectional thyristor), an eighth switch S8 (preferably a diode; or a controllable switch provided by a control unit with a control signal, such as a unidirectional thyristor), and a sixth element R6 (a resistor), wherein the second element R2 (optional), the third switch S3, the third capacitor C3, the fifth switch S5, the first element R1 (optional), and the second switch S2 are used for charging the third capacitor C3 to the circuit shown in FIG. 3; a sixth series circuit is formed by a sixth switch S6, a third capacitor C3, an eighth switch S8 (optional) and a fourth switch S4, in the breaking process of the mechanical switch K, the second power supply supplies power to the load RL through the sixth series circuit, and in the breaking process of the mechanical switch K, two arc extinguishing control modes can be adopted, wherein the first mode is an arc extinguishing mode (used for improving the reliability of arc extinguishing of the mechanical switch K connected with a heavy-current load) that the first capacitor C1 and the third capacitor C3 simultaneously supply power to the load RL; the second one is an arc extinguishing mode that the first capacitor C1 and the third capacitor C3 are used for supplying power to the load RL in sequence, so that arc extinguishing can be performed on the same mechanical switch K (the reliability of arc extinguishing of the mechanical switch K is improved, the reignition of the arc is prevented, and the arc extinguishing mode is particularly suitable for arc extinguishing of mechanical switches which do not have the breaking force of working current per se), or arc extinguishing can be performed on different mechanical switches K, so that the response speed of secondary arc extinguishing can be greatly improved, the discharging process of the first capacitor C1 can be referred to for discharging of the third capacitor C3, the discharging circuit of the third capacitor C3 shares the discharging circuit of the first capacitor C1, and the charging circuit of the third capacitor C3 shares the charging circuit of the first capacitor C1, so that the circuit is greatly simplified, the cost is reduced, and the volume is reduced.

A power source (a power source at the input end of the mechanical switch K, which may be provided by another power source) is connected to the common end of the eighth switch S8 and the fourth switch S4 through a sixth element R6 (whose resistance is such that the current passing through the sixth element R6 is smaller than the minimum holding current of the fourth switch S4), and a series circuit of a first capacitor C1 and an eighth switch S8 is connected to the first switch S4, so that after the first capacitor C1 completes supplying power to the load RL or before the first capacitor C1 is charged, the control unit U can quickly detect whether the fourth switch S4 breaks down according to the voltage at the common end, and prevent the third switch S3 from failing to turn off when the first capacitor C1 is charged, or can connect a photocoupler (defined as a second photocoupler, which detects the voltage between the common end and the sixth element R6) in series with the sixth element R6, and the output signal of the photocoupler is transmitted to the control unit U, as a test whether the fourth switch S4 breaks down.

In a second embodiment of the arc extinguishing device of the present invention, an arc extinguishing device includes the second embodiment of the arc extinguishing circuit of the present invention:

the arc extinguishing device (namely, an intelligent mechanical switch management system) is suitable for single or multi-path mechanical switch electric control systems of new energy automobiles, rail transit, aviation, automatic control and the like, and further comprises a control unit U, wherein control signals of a first switch S1, a second switch S2, a third switch S3, a fourth switch S4 and a sixth switch S6 (shown in figure 4, optional) are provided by the control unit U; the voltage signal of the first capacitor C1 is transmitted to the control unit U for detecting the operating states (breakdown, on, off) of the first switch S1, the second switch S2, the third switch S3, and the fourth switch S4; the voltage signal of the first capacitor C1 may be a voltage signal between two ends of the first capacitor C1, or may be a voltage signal between two ends of the first capacitor C1 to ground; the voltage signal (through the terminal B) of the power supply at the input end of the mechanical switch K and the voltage signal (through the terminal C) at the common end of the mechanical switch K and the load RL are transmitted to the control unit U.

The working principle is as follows: after the input terminal of the mechanical switch K is powered on, the control unit U provides a control signal to the second switch S2 (for controlling conduction), a pulse signal triggers the third switch S3 to conduct, the first capacitor C1 is charged, and the control unit U can adjust the charging voltage of the first capacitor C1 by detecting the voltage at the a terminal point and obtain the capacity of the first capacitor C1 (for determining whether the capacity of the first capacitor C1 is normal, and optimizing the arc extinguishing control program according to the collected data) during the whole charging process of the first capacitor C1, whether the fourth switch S4 breaks down or not can be known by detecting the charging voltage of the first capacitor C1 (if there is a breakdown, the control unit U does not conduct another fourth switch S4, or a detection unit for detecting the charging current of the first capacitor C1 can be added, and an output signal of the detection unit is transmitted to the control unit U for detecting whether the fourth switch S4 breaks down or not). In the process of closing the mechanical switch K, the control unit U provides a pulse signal to trigger the third switch S3 and the fourth switch S4 to be turned on (the control process can be selected as required), and the control unit U can know whether the third switch S3 and the fourth switch S4 are turned off or not by detecting the voltage of the terminal a (i.e., the common terminal of the third switch S3 and the fourth switch S4), and if the voltage is turned off, the mechanical switch K is turned on (or the capacitive load is fully charged);

in the process of breaking the mechanical switch K, the third switch S3 is in an off state (for example, when the third switch S3 is a fully-controlled device, it may also be in an on state), the control unit U detects that the contact of the mechanical switch K is off (the voltage at the common end of the mechanical switch K and the load RL can be detected, or the contact of the mechanical switch K is off detected by using an auxiliary switch of the mechanical switch K), and then controls the first switch S1 (or the sixth switch S6) and the fourth switch S4 to be on, and the built-in microcontroller can complete time delay (optional) to control the first switch S1 (or the sixth switch S6) and the fourth switch S4 to be on, the time value of the time delay is related to the breaking speed of the corresponding mechanical switch K, so that when a certain opening distance exists between the contacts of the mechanical switch K, the first capacitor C1 starts to discharge, and the precharge voltage of the first capacitor C1 is prevented from forming a loop through the mechanical, the control unit U can know the working states (on or off) of the first switch S1 and the fourth switch S4 by detecting the voltage of an A (F) endpoint (namely the common end of a series circuit consisting of the first switch S1 and the first capacitor C1 and the fourth switch S4 or a D endpoint), so as to judge whether the first capacitor C1 finishes forward charging or not, and prepare for discharging the first capacitor C1.

In this embodiment, the first power supply and the second power supply are both provided by two ends of the first series circuit, and the power supply has the advantages of simple circuit and high cost performance.

The embodiment can realize arc extinguishing voltage promotion under the conditions that a transformer and a single capacitor are not needed, and the charging voltage of the capacitor is not higher than the working voltage of a system, and has the advantages of simple circuit, small size and high reliability.

One of three schematic diagrams of the arc extinguishing circuit embodiment of the invention is shown in fig. 5:

a mechanical switch K required for arc extinction and a load RL are connected in series to form a first series circuit, and the first series circuit comprises a first switch S1, a first capacitor C1, a first charging unit U1 (formed by connecting a first element R1 and a second switch S2 in series), a second capacitor C2 and a second charging unit U2 (formed by connecting a second element R2 and a seventh switch S7 in series).

When the mechanical switch K is closed, a first power supply (provided by power supplies connected to two ends of the load RL, provided by an output end of the mechanical switch K, or provided by another power supply) connected to the first series circuit charges the first capacitor C1 through the first charging unit U1, and simultaneously the first power supply charges the second capacitor C2 through the second charging unit U2, and in the breaking process of the mechanical switch K, the second power supply (provided by the second capacitor C2) supplies power to the load RL through the first switch S1 and the first capacitor C1 (the voltage of the second capacitor C2 is superposed with the voltage of the first capacitor C1), so that the arc extinction of the mechanical switch K is achieved. Note: the first element R1 and the second switch S2 of the first charging unit U1 can be selected as one; the second element R2 and the seventh switch S7 (a unidirectional thyristor or a diode) of the second charging unit U2 can be selected as one; when the second capacitor C2 is charged with charges, the second charging unit U2 may be omitted.

The embodiment has the advantages of simple circuit, high cost performance and good safety.

Fig. 6 shows a second schematic diagram of the third embodiment of the arc extinguishing circuit of the present invention and a third schematic diagram of the arc extinguishing device of the present invention:

an arc extinguishing circuit, fig. 6 is a third series circuit formed by adding a third switch S3, a fourth switch S4, a fourth capacitor C4, a first diode D1, a second diode D2, a fourth element R4 (resistor) and a fifth element R5 (resistor) to fig. 5, wherein the second element R2 (optional), the third switch S3 (optional), the first capacitor C1, the first element R1 (optional) and the second switch S2, and the third series circuit is used for charging the first capacitor C1; the first power supply connected to the first series circuit (provided by the power supply connected across the first series circuit, or by another power supply) charges the first capacitor C1 through the third series circuit, meanwhile, the first power supply charges a second capacitor C2 through a second element R2, a third switch S3 and a seventh switch S7 (a unidirectional thyristor, or a diode and a resistor which are connected in series), the first switch S1, the first capacitor C1 and the fourth switch S4 form a second series circuit, and in the breaking process of the mechanical switch K, the second power supply provided by the second capacitor C2 supplies power to the load RL via the second series circuit for the purpose of extinguishing the arc of the mechanical switch K, if the charge of the first capacitor C1 is smaller than the charge of the second capacitor C2, after the first capacitor C1 is discharged, the second capacitor C2 is discharged through the first switch S1, the first diode D1, the fourth switch S4 and the load RL; if the charge of the first capacitor C1 is greater than the charge of the second capacitor C2, after the second capacitor C2 is discharged, the first capacitor C1 is discharged through the fourth switch S4, the load RL and the second diode D2.

The second element R2 (optional), the third switch S3 and the fourth switch S4 form a fourth series circuit, before or during the closing of the mechanical switch K, the first power supply supplies power to the load RL through the fourth series circuit, so as to close and extinguish the arc of the mechanical switch K, or pre-charge the load RL (such as a capacitive load, a motor controller, a dc converter and the like), so that the current impact of the capacitive load on the mechanical switch K can be effectively overcome, and the following steps are performed: before the mechanical switch K is closed, the first capacitor C1 may not be charged, and only the second capacitor C2 is charged, and during the closing process of the mechanical switch K, if the first switch S1 and the seventh switch S7 are also turned on, the closing bounce arc extinguishing effect of the mechanical switch K is better, because the second capacitor C2 simultaneously keeps supplying power to the load RL, and the third switch S3 simultaneously supplements the charging of the second capacitor C2.

Note: when the first power is not supplied by the power connected to the first series circuit and is inputted from the terminal a, the second element R2 and the third switch S3 are selected as required.

The third embodiment of the arc extinguishing device of the invention:

an arc extinguishing device comprising a third embodiment of an arc extinguishing circuit: the arc extinguishing device is suitable for single or multi-path mechanical switch electric control systems (namely, a mechanical switch intelligent management system) of new energy automobiles, rail transit, aviation, automatic control and the like, and further comprises a control unit U, wherein control signals of a first switch S1, a second switch S2, a third switch S3, a fourth switch S4 and a seventh switch S7 are provided by the control unit U; the voltage signal of the first capacitor C1 is transmitted to the control unit U for detecting the operating states (breakdown, on, off) of the first switch S1, the second switch S2, the third switch S3, and the fourth switch S4; the voltage signal of the first capacitor C1 may be a voltage signal between two ends of the first capacitor C1, or may be a voltage signal between two ends of the first capacitor C1 to ground; the voltage of the second capacitor C2 is transmitted to the control unit U; the voltage signal of the power supply at the input of the mechanical switch K is transmitted (via the B terminal) to the control unit U.

The working principle is as follows: after the input terminal of the mechanical switch K is powered on, the control unit U provides a control signal to the second switch S2 (for controlling conduction), a pulse signal triggers the third switch S3 and the seventh switch S7 to conduct, so as to charge the first capacitor C1 and the second capacitor C2, during the whole charging process of the first capacitor C1, the control unit U can adjust the charging voltage of the first capacitor C1 by detecting the voltage at the a terminal, and can obtain the capacity of the first capacitor C1 (for determining whether the capacity of the first capacitor C1 is normal, and optimizing an arc extinction control program according to the collected data), can obtain whether the fourth switch S4 is broken down by detecting the charging voltage of the first capacitor C1 (if a breakdown condition exists, the control unit U will not conduct another fourth switch S4, or can add a detection unit for detecting the charging current of the first capacitor C1, and the output signal of the detection unit is transmitted to the control unit U, for detecting whether the fourth switch S4 breaks down); the control unit U can detect the voltage of the E endpoint and can obtain the capacity of the second capacitor C2 (used for judging whether the capacity of the second capacitor C2 is normal or not and optimizing an arc extinction control program according to collected data), and can obtain whether the fourth switch S4 is broken down or not through detecting the charging voltage of the second capacitor C2 (if the breakdown condition exists, the control unit U does not conduct control on the other fourth switch S4); in the closing working process of the mechanical switch K, the control unit U provides a pulse signal to trigger the third switch S3 and the fourth switch S4 to be turned on (the control process can be selected as required), and the control unit U can know whether the third switch S3 and the fourth switch S4 are turned off or not by detecting the end point a, and if the third switch S3 and the fourth switch S4 are turned off, the mechanical switch K is turned on (or the capacitive load is fully charged);

in the process of breaking the mechanical switch K, the third switch S3 is in an off state (for example, when the third switch S3 is a fully-controlled device, it may also be in an on state), the control unit U detects that the contact of the mechanical switch K is off (the voltage at the common end of the mechanical switch K and the load RL can be detected, or the contact of the mechanical switch K is off is detected by using an auxiliary switch of the mechanical switch K), the first switch S1 and the fourth switch S4 are controlled to be on by delaying (optionally), the microcontroller can complete delaying control, the time value of the delaying is related to the breaking speed of the corresponding mechanical switch K, so that when a certain opening distance exists between the contacts of the mechanical switch K, the first capacitor C1 starts to discharge, the arc reignition is prevented, and the reliability of arc extinction is improved, the control unit U detects an end point a (that is the common end of the series circuit formed by the first switch S1 and the first capacitor C1 and the fourth switch S4, or point D), it can be known whether the first switch S1 and the fourth switch S4 are in the on state, the voltages at the two ends of the load RL are increased, the electric field strength between the contacts of the mechanical switch K is rapidly decreased, so as to achieve the purpose of rapidly extinguishing the arc of the mechanical switch K, the control unit U can determine whether the first capacitor C1 finishes discharging by detecting the voltage at the point a (or point D) to know whether the first switch S1 and the fourth switch S4 are in the off state, so as to prepare for next charging of the first capacitor C1. Note: in the arc extinguishing working process, when the first capacitor C1 finishes discharging and the mechanical switch K still has an arc (the first switch S1 is turned off, the fourth switch S4 is turned off, the second capacitor C2 cannot discharge, and the control unit U can know that the voltage of the a endpoint and the voltage of the E point of the second capacitor C2 are detected), the control unit U provides a pulse signal to trigger the third switch S3, the second switch S2 and the seventh switch S7 to be turned on, the first capacitor C1 and the second capacitor C2 are charged again, and then the arc extinguishing working process is performed again, in the next working process, the control unit U raises the charging voltage of the first capacitor C1, or the control unit U adjusts the delay time.

The first capacitor C1 of this embodiment may be connected to the optocoupler voltage detection unit shown in fig. 2, and is configured to detect a charging voltage of the first capacitor C1.

Fig. 7 shows a third schematic diagram of an embodiment of an arc extinguishing circuit of the present invention and a fourth schematic diagram of an embodiment of an arc extinguishing device of the present invention:

an arc extinguishing circuit, fig. 7 is an arc extinguishing circuit, in which a third switch S3, a fourth switch S4, a third element R3 (resistor or inductor), a fourth capacitor C4, a first voltage stabilizing device Z1 (a voltage stabilizing diode, or a voltage sensitive, or a resistor for stabilizing voltage), a first diode D1, a second switch S2 (second diode), a fourth element R4 (resistor), and a fifth element R5 (resistor) are added on the basis of fig. 5;

a third element R3 (optional), a third switch S3 (optional), a first capacitor C1, a second switch S2 (uncontrolled switch, diode; or a semi-controlled switch such as a unidirectional thyristor), and a second capacitor C2 form a third series circuit; a first power supply connected with the first series circuit (provided by power supplies connected with two ends of the first series circuit, or provided by another power supply) charges the first capacitor C1 and the second capacitor C2 through a third series circuit, and the first power supply charges the second capacitor C2 through a third element R3 (optional), a third switch S3, a second element R2 and a seventh switch S7 (an uncontrolled switch, a diode; or a semi-controlled switch such as a unidirectional thyristor is adopted, and the second element R2 and the seventh switch S7 form a second charging unit); the first voltage-stabilizing device Z1 (or a resistor) is connected in parallel with the first capacitor C1 and used for limiting the voltage at two ends of the first capacitor C1, the eighth series circuit is composed of the third element R3 (optional), the third switch S3 (optional), the first capacitor C1 and the first element R1 (first charging unit), and the first power supply charges the first capacitor C1 through the eighth series circuit; the first switch S1, the first capacitor C1 and the fourth switch S4 form a second series circuit, and in the disjunction process of the mechanical switch K, a second power supply provided by the second capacitor C2 supplies power to the load RL through the second series circuit, so that the aim of arc extinction of the mechanical switch K is fulfilled;

the capacity of the first capacitor C1 is greater than the capacity of the second capacitor C2 (the capacity of the first capacitor C1 is greater than twice the capacity of the second capacitor C2), the charge of the first capacitor C1 is greater than the charge of the second capacitor C2, and after the second capacitor C2 discharges, the first capacitor C1 discharges through the fourth switch S4, the load RL, the first diode D1 and the first switch S1;

if the design that the capacity of the second capacitor C2 is greater than the capacity of the first capacitor C1 (the capacity of the second capacitor C2 is greater than twice the capacity of the first capacitor C1) is adopted, the charge of the second capacitor C2 is greater than the charge of the first capacitor C1, after the first capacitor C1 discharges, the second capacitor C2 discharges through the first switch S1, the fourth diode D4, the fourth switch S4 and the load RL, and the first voltage stabilizing device Z1 is connected in parallel with the second capacitor C2 instead.

The charging mode that the first capacitor C1 and the second capacitor C2 are connected in series is adopted, so that the charging device has the advantages of high charging speed and low loss.

Note: when the first power is not supplied by the first series circuit connected power source and is input from the a terminal, the third element R3 and the third switch S3 are selected as required.

The third element R3 (optional), the third switch S3 and the fourth switch S4 form a fourth series circuit, and before or during the closing of the mechanical switch K, the first power supply supplies power to the load RL through the fourth series circuit, so that the mechanical switch K is used for closing and extinguishing the arc, or the load RL is used for pre-charging (such as a capacitive load, a motor controller, a direct current converter and the like), and the current impact of the capacitive load on the mechanical switch K can be effectively overcome.

In a fourth embodiment of the arc extinguishing device of the present invention, an arc extinguishing device includes the arc extinguishing circuit described above:

an arc extinguishing device (namely an intelligent management system of a mechanical switch) suitable for single or multi-path mechanical switch electric control systems of new energy automobiles, rail transit, aviation, automatic control and the like also comprises a control unit U, wherein control signals of a first switch S1, a second switch S2, a third switch S3 and a fourth switch S4 are provided by the control unit U; a voltage signal of the first capacitor C1 (a series circuit of the first capacitor C1 and the second capacitor C2) is transmitted to the control unit U for detecting the working states (breakdown, on, off) of the first switch S1, the third switch S3 and the fourth switch S4; the voltage signal of the power supply at the input of the mechanical switch K is transmitted (via the B terminal) to the control unit U.

The working principle is as follows: after the input end of the mechanical switch K is powered on, the control unit U provides a pulse signal to trigger the third switch S3 to be turned on, and charges the first capacitor C1 and the second capacitor C2, and in the whole charging process, the control unit U can obtain the capacitance of the series circuit of the first capacitor C1 and the second capacitor C2 by detecting the voltage (for judging whether the capacities of the first capacitor C1 and the second capacitor C2 are normal, and optimizing an arc extinction control program according to the collected data); the control unit U can detect the voltage at the D terminal (or E terminal) and know the capacity of the second capacitor C2 (for determining whether the capacity of the second capacitor C2 is normal, and optimizing the arc extinguishing control program according to the collected data); in the process of closing the mechanical switch K, the control unit U provides a pulse signal to trigger the third switch S3 and the fourth switch S4 to be turned on (the control process can be selected as required), and the control unit U can know whether the third switch S3 and the fourth switch S4 are turned off or not by detecting the voltage of the terminal a (i.e., the common terminal of the third switch S3 and the fourth switch S4), and if the voltage is turned off, the mechanical switch K is turned on (or the capacitive load is fully charged);

in the process of breaking the mechanical switch K, the third switch S3 is in an off state (or in an on state if the third switch S3 is a fully-controlled device), the control unit U detects that the contact of the mechanical switch K is off, the first switch S1 and the fourth switch S4 are controlled to be on in a delayed (optional) manner, the delay control can be completed by a built-in microcontroller, the time value of the delay is related to the breaking speed of the corresponding mechanical switch K, so that when a certain opening distance exists between the contacts of the mechanical switch K, the first capacitor C1 starts to discharge, the arc reignition is prevented, the reliability of arc extinction is improved, the voltage at the two ends of the load RL rises, the electric field intensity between the contacts of the mechanical switch K drops rapidly, and the purpose of rapidly extinguishing the arc of the mechanical switch K is achieved, the control unit U can detect the a end point (namely, the common end of the series circuit consisting of the first switch S1 and the first capacitor C1, and the, or point D), whether the first switch S1 and the fourth switch S4 are in the off state is known, so as to determine whether the first capacitor C1 is completely discharged, and prepare for charging the first capacitor C1 next time. Note: in the arc extinguishing working process, when the first capacitor C1 finishes discharging and the mechanical switch K still has an arc (the first switch S1 is turned off, the fourth switch S4 is turned off, the second capacitor C2 or the first capacitor C1 cannot discharge completely), the control unit U provides a pulse signal to trigger the third switch S3 to be turned on, the first capacitor C1 and the second capacitor C2 are charged again, then the arc extinguishing working process is carried out again, and in the next working process, the control unit U adjusts the delay time.

A fourth capacitor C4 (the grounding end of the fourth capacitor C4 can be changed to be connected in series with a controllable semiconductor switch, and the fourth capacitor C4 is connected in parallel with the third switch S3 through the controllable semiconductor switch, wherein the controllable semiconductor switch is preferably a unidirectional thyristor, a control signal of the controllable semiconductor switch is provided by the control unit U, and the controllable semiconductor switch is defined as an eleventh switch) connected to a common end of the second element R2 (shown in fig. 6; or the third element R3, shown in fig. 7) and the third switch S3, and is used for overcoming over-voltage caused by the mechanical switch K input power line due to over-fast current interruption and over-voltage caused by the mechanical switch K input power line, and preventing the third switch S3 from being turned on by mistake and broken; a power supply (the power supply at the input end of the mechanical switch K) is respectively connected with the first capacitor C1 and the second capacitor C2 through the fourth element R4 and the fifth element R5, so that the first capacitor C1 and the second capacitor C2 are charged in a complementary manner without frequently controlling the conduction of the third switch S3, and the influence on the arc extinguishing response speed is overcome; the current passing through the fourth element R4 and the fifth element R5 is smaller than the minimum holding conduction current of the third switch S3 (e.g. using a half-controlled device) and the fourth switch S4, and the fourth element R4 and the fifth element R5 can be omitted when the third switch S3 uses a fully-controlled device.

Fig. 6 and 7 can refer to the added circuit of the sixth element R6 and the eighth switch S8 shown in fig. 4 to achieve the same technical effect (see the related description of the embodiment of the invention).

The terminal a and the terminal K of fig. 6 and 7 are connected in series with a ninth switch S9 (a controllable switch, which uses a unidirectional thyristor, and a control signal of the unidirectional thyristor is provided by the control unit U) as shown in fig. 8, that is, the first capacitor C1 and the ninth switch S9 form a series circuit, and a voltage signal of a common terminal (terminal a) of the series circuit and the third switch S3 and the fourth switch S4 is connected to the control unit U, so that the working states (on, off, breakdown, and are not affected by the fourth element R4, the fifth element R5 and the first capacitor C1) of the third switch S3 and the fourth switch S4 can be detected conveniently, and high-resolution AD acquisition and high-low level acquisition are not required, and a tenth switch S10 (a diode) connected (in parallel) with the ninth switch S9 can be omitted when the ninth switch S9 uses a bidirectional thyristor. Note: the tenth switch S10 is not limited to be connected in parallel with the ninth switch S9, and the anode of the tenth switch S10 (e.g., a unidirectional thyristor, the control signal of which is provided by the control unit U) may be connected to the input power terminal of the mechanical switch K through a current limiting element (e.g., the second element R2 of fig. 6, or the third element R3 of fig. 7).

The charging power of the first capacitor C1 and the second capacitor C2 is provided by the power (first power) connected with the two ends of the first series circuit, and the second power is provided by the second capacitor C2, so that the charging circuit has the advantages of simple circuit, high cost performance and good safety; when the system voltage is higher, the first capacitor C1 adopts an electrolytic capacitor, and the second capacitor C2 adopts a non-polar capacitor, so that the volume and the cost can be greatly reduced.

In the arc extinguishing device of the present invention, the fourth switch S4 is not limited to the control signal provided by the control unit U, and the control pole of the fourth switch S4 may be connected to the ground through a capacitor (fifth capacitor) or connected to the input terminal of the mechanical switch K through a capacitor (fifth capacitor) for detecting the breaking of the mechanical switch K, and the third switch S3 proposes a fully controlled switch.

In the second, third and fourth embodiments of the arc-extinguishing device, when two or more than two fourth switches exist, the control unit suggests to detect the working states (on, off and breakdown) of the fourth switches, and suggests that each fourth switch is connected with at least one diode in series, so that the working safety of the system is ensured.

The invention relates to a control unit U of an arc extinguishing device:

a programmable device (such as a microcontroller) is arranged in the circuit, and in order to simplify a control unit circuit, the programmable device can be designed in common with a load RL, so that the non-electrical isolation (non-photoelectric isolation and non-electromagnetic isolation) AD acquisition, level acquisition or voltage comparison of each voltage signal is facilitated; for example, the AD acquisition is performed on an a terminal, a B terminal, a C terminal, a D terminal, an E terminal (if present), and an F terminal (if present) (voltage signals of each terminal are transmitted to an input port of the programmable device through resistance voltage division, and voltage signals of each terminal are voltage signals of each terminal to ground); or level acquisition (voltage signals of each endpoint are transmitted to an input port of the programmable device through a transistor output signal by a resistor driving transistor, and the voltage signals of each endpoint are voltage signals of each endpoint to ground); or voltage comparison (voltage across the mechanical switch K); the second switch S2 (or the third switch S3) is controlled by the programmable device, and a voltage signal common to the mechanical switch K and the load RL is also provided to the control unit U (the voltage signal can be a voltage across the mechanical switch K, across the fourth switch S4, across the load RL;)

When the programmable device selects the design of electrical isolation (photoelectric isolation and electromagnetic isolation) with the load RL, the control unit U can collect each voltage signal through the photoelectric coupler; if level collection is carried out on each end point (voltage signals of each end point drive a photoelectric coupler through a resistor, output signals of the photoelectric coupler are transmitted to an input port of the programmable device, and voltage signals of each end point are voltage signals of each end point to ground), meanwhile, common end voltage signals of the mechanical switch K and the load RL can also be provided for the control unit U through the photoelectric coupler (the voltage signals can be voltages of two ends of the mechanical switch K, two ends of the fourth switch S4 and two ends of the load RL, the voltage signals can drive the photoelectric coupler through the resistor, and output signals of the photoelectric coupler are transmitted to the input port of the programmable device);

the intelligent unit of the control program is built in the control unit U, under the condition that hardware resources are not increased or few hardware resources are increased, the control mode of the multi-path load RL is adjusted according to different conditions (capacitive, inductive, resistive and current) of the multi-path load RL, the arc extinguishing effect is improved, the electric service life of the multi-path mechanical switch K is effectively prolonged, timing (time delay control switch and switch conduction), A/D (or level) collection, voltage comparison (such as voltages at two ends of the mechanical switch), logic processing, charging and discharging of the first capacitor C1 (or the third capacitor C3 or the second capacitor C2) and the like can be finished, and the circuit simplification is facilitated; the shared first capacitor C1 (or the third capacitor C3, the second capacitor C2), the control unit U controls the arc extinction of the multi-path mechanical switch K (the mechanical switches can be connected in series or in parallel), the closing arc extinction of the mechanical switch K (or the pre-charging of the load RL) and the detection (the closing state, the opening state, the arc extinction, and whether the states are stable and normal) are carried out, the service life of the mechanical switch K is calculated according to the arc extinction condition and the operation times of the mechanical switch K, and the related information (fault codes, the operation times of the mechanical switch, the electrical life, the mechanical life, the working state and the like) is transmitted or displayed, thereby being beneficial to improving the overall safety of an electric control system, being convenient to maintain and having the characteristic of higher cost performance, being widely applied to the fields of new energy vehicles, rail transit, ships, aviation, automatic control and the like, serving as a new capacitor with the, The intelligent management system for the mechanical switch comprises a mechanical switch service life calculation and service life end prediction and a mechanical switch working state detection.

Because the electrical characteristics of the multi-path mechanical switch K and the multi-path load RL connected with the control unit U are not necessarily consistent, in order to achieve the optimal arc extinguishing effect, the control unit U stores parameters related to the current of the load RL, or inputs parameters or signals related to the current of the load RL, or action time parameters of the mechanical switch K, the charging voltage of the first capacitor C1 is in direct proportion to the current passing through the mechanical switch K needing arc extinguishing (the control unit U controls the second switch S2 to adjust the charging voltage), in the breaking work process of the mechanical switch K, the time of delayed conduction of the first switch S1 and the fourth switch S4 is in direct proportion to the current of the load RL, and the time parameter of the delay can be completed by a programmable device arranged in the control unit U; the method is favorable for overcoming the influence of overvoltage on the system in the arc extinguishing process and achieving the best arc extinguishing effect.

A control signal of the mechanical switch K (not limited to be provided by a control end of the mechanical switch K, but also provided by a port J2) is transmitted to the control unit U, or the control signal of the mechanical switch K is provided by the control unit U, or an auxiliary switch signal of the mechanical switch K is transmitted to the control unit U, so that the fourth switch S4 and the third switch S3 are controlled to be switched on in advance before the mechanical switch K is closed, arc extinguishing accuracy and real-time performance are improved, and action logic and arc extinguishing control logic of each mechanical switch are optimized and selected according to needs;

the control unit U is used for recording the operation times of the mechanical switch, and the control unit U detects that the contact of the mechanical switch K is disconnected.

The control unit U can comprise a display unit or be connected with the display unit (can adopt communication port connection) and is used for displaying information such as the action state of the mechanical switch K, the operation times of the mechanical switch K, the arc extinguishing action state, the residual service life (mechanical service life and electrical service life) of the mechanical switch K and the like; the control unit U may include an input unit (keys, etc.) or may be connected to an input unit (which may be connected using a communication port).

The mechanical switch K for arc extinction required by the arc extinction device can adopt mechanical switches (relays, contactors, travel switches and the like) which do not have breaking force (voltage and current breaking force) under working conditions, so that the aims of greatly reducing cost, lightening weight and reducing the volume of the mechanical switches are fulfilled;

meanwhile, compared with a mechanical switch with breaking force, the mechanical switch without breaking force has slower breaking and closing speed of a mechanical contact, smaller mechanical impact and longer operating electric life, when the mechanical switch is in a motion state and under the working condition that unexpected mechanical impact (such as collision, car turnover and the like) is possible to occur, the mechanical switch K is possible to be accidentally closed and broken under a normally open state, or the opening distance is shortened, or impact voltage occurs at two ends of the mechanical switch K, at this time, arcing is possible to occur, and when the control unit U detects the arcing under the breaking state of the mechanical switch K, the control unit U controls the first switch S1 and the fourth switch S4 to be conducted to extinguish the arc.

When the number of the mechanical switches K, the load RL and the fourth switch S4 is two or more, the first capacitor C1, the first switch S1, the second switch S2, the third switch S3 and the control unit U are shared (share a programmable device), so that the purposes of greatly saving cost and reducing volume can be achieved, meanwhile, the arc extinguishing voltage is higher than the working voltage of the load RL, and the line loss caused by the overlong circuit of the first capacitor C1 relative to each load RL due to the distributed layout of the multiple mechanical switches K can be effectively overcome, so that sufficient arc extinguishing current can be provided, and the arc extinguishing effect can be improved; the arc extinguishing current effective value is limited by adopting a capacitor (the first capacitor C1 can also be connected with a current limiting element in series, such as an inductor, and can also limit the rising rate of the arc extinguishing current and reduce the peak current), so that the risk of power supply to other loop loads RL caused by breakdown of a certain fourth switch S4 is prevented; the common ends of the mechanical switches K required to extinguish arc and the load RL are connected through the fourth switch S4, the fourth switches S4 of each path are connected in series in a reverse direction (the withstand voltage value is the sum of the withstand voltage values of the two fourth switches S4), the problem that the mechanical switch K supplies power to the load RL connected with the other path of mechanical switch K due to misconduction does not exist, and the device has the advantages that the withstand voltage between the output ends of the mechanical switches K of each path is high (the withstand voltage can easily reach 4000 volts when the fourth switch S4 adopts a unidirectional thyristor), the response speed is high (by selecting the first capacitor C1 with proper capacity, the device can easily meet the requirement of breaking the arc for dozens of or more than one hundred times within 1 second), the size is small, the cost is low, the limitation of the arc extinguishing operation times does not exist, and the like; in order to further improve the safety when the system voltage is higher, the fourth switch S4 may be formed by connecting one or more diodes (the conventional withstand voltage may reach 1000 to 2000 volts, and a diode with a rated current of 10 amps may be used to extinguish the arc of the mechanical switch with the current of last kiloamp) in series with a half-controlled device (such as a unidirectional thyristor, the conventional type withstand voltage of which may reach 1500 to 2000 volts, and a unidirectional thyristor with a rated current of 25 amps is used to extinguish the arc of the mechanical switch with the current of last kiloamp), and is defined as a ninth series circuit (the connection relationship between the ninth series circuits is a reverse series relationship, as shown in fig. 9), which can greatly improve the withstand voltage between the output ends of the mechanical switches (easily reaching 6000 volts, or more than ten thousand volts), and has the advantages of low cost, high withstand voltage capability, strong overcurrent capability, and high reliability.

In the above embodiments, the first element R1, the second element R2, and the third element R3 are used as current limiting elements, are resistors, may also be inductors, or are disconnectable (fusing) elements used for protection when one or two of the second switch S2, the third switch S3, and the fourth switch S4 are abnormally turned on, and are used for current limiting or disconnection protection, and are selected according to needs (or used selectively, and may be omitted when other current limiting elements exist in the line); the first capacitor C1 is connected in series with an inductor as a charging current limiter, and the control unit U drives the second switch S2 (and the third switch S3 is also a fully-controlled switch, or a mechanical switch) to charge the first capacitor C1 by using pulses (pulse groups), so as to adjust the charging voltage of the first capacitor C1.

In the above embodiment, the first switch S1, the second switch S2, the third switch S3, the fourth switch S4, and the sixth switch S6 (the fifth switch S5) are preferably controllable switches (semiconductor switches, controllable semiconductor devices), the third switch S3 may be a half-controlled switch (semiconductor switches, half-controlled semiconductor devices, unidirectional thyristors), or a full-controlled switch (semiconductor switches, full-controlled semiconductor devices, which may be used to adjust the charging voltage of the first capacitor C1), which has the advantage of fast response speed; the first switch S1, the fourth switch S4, and the sixth switch S6 are preferably half-controlled switches (semiconductor switches, half-controlled semiconductor devices, and the control unit U drives the half-controlled switches to conduct through a transformer), have extremely high overload force (when the first switch S1 and the fourth switch S4 adopt one-way thyristors with rated operating currents of 25 amperes, a mechanical switch K passing hundreds of amperes or even thousands of amperes of current can be safely and reliably extinguished), and have the advantages of positive and negative withstand voltage, low cost, and convenient control (pulse triggering of the transformer); when the second switch S2 (or the third switch S3) is a fully-controlled switch (a fully-controlled semiconductor device, such as a triode, a field effect transistor, an IGBT), the charging voltage of the first capacitor C1 is conveniently adjusted (it is recommended that the charging voltage is not more than 50% of the working voltage of the load RL, the charging voltage can be adjusted according to the magnitude of the current of the load RL, the charging voltage is the voltage at two ends of the first capacitor C1, and the influence of the overvoltage on the load RL is prevented, and during the breaking of the mechanical switch K, the pulse voltage provided by the first capacitor C1 (or a series circuit formed by the second capacitor C2, the first switch S1 and the first capacitor C1) to the load RL is greater than the working voltage of the load RL and not more than 2 times (preferably not more than 1.5 times) of the working voltage of the load RL.

In the above embodiment, under the condition that the control unit U detects that the arc extinction fails (by detecting whether the control unit U detects that the first switch S1 or the fourth switch S4 is turned off or not; or known according to the voltage of the first capacitor C1; or known according to the voltages of the first capacitor C1 and the second capacitor C2), the second switch S2 (or the third switch S3; or the second switch S2 and the third switch S3) is used to charge the first capacitor C1 again, and then the second arc extinction is performed, so that the reliability of the arc extinction and the response speed of the second arc extinction can be greatly improved.

On the basis of the above embodiment, the mechanical switch K may be connected in series with a unidirectional conducting device (diode or unidirectional thyristor) for preventing the backward flow of the first capacitor C1, and when the current is large, the unidirectional conducting device may be connected in parallel with a bypass switch (mechanical switch), and a control signal of the bypass switch is provided by the control unit U.

In the above embodiment, the J1 can be connected with an external power port (optional); j2 is a communication port for transmitting and receiving related information.

Fig. 10 shows an arc extinguishing apparatus according to a fifth embodiment of the present invention:

the arc extinguishing device is placed in a shell, serves as a product with strong universality, is connected with each external mechanical switch and an upper computer through terminals, is convenient to safely authenticate, is popularized and popularized, and can be flexibly designed according to the specific appearance.

In the above embodiment, when the number of the mechanical switch K, the load RL, and the fourth switch S4 is two or more, the first capacitor C1, the first switch S1, the second switch S2, the third switch S3, and the control unit U (sharing a programmable device) are shared, and the semiconductor device is used to connect the loads of each path, so as to achieve the purposes of greatly saving cost, reducing volume, and increasing the response speed of electronic arc extinguishing, which is not only an intelligent electronic arc extinguishing system with an increased mechanical switch electrical life, but also a multi-path mechanical switch intelligent management system with functions of mechanical switch life calculation, life end prediction, mechanical switch operation frequency recording, and mechanical switch working state detection without increasing hardware resources, and can also greatly reduce the manual maintenance cost and the operation cost of the system (electronic control system), and improve the safety of the system operation, the intelligent level of the equipment is improved, a heavy and expensive mechanical switch with high breaking force is not needed (the original electrical design standard is changed), the environmental pollution caused by frequent switch replacement is reduced, the economic value and the social value are very high, and the current situation that electronic arc extinguishing is difficult to popularize is greatly facilitated to change.

Sixth embodiment of the arc extinguishing apparatus of the present invention is shown in fig. 11:

an arc extinguishing device is characterized in that a mechanical switch K required to extinguish arc is connected with a load RL in series to form a first series circuit, the first series circuit comprises a first switch S1, a first capacitor C1, a first charging unit U1 (a first element R1 and a resistor), a second charging unit U2 (a second diode D2 is connected with a second element R2 in series or alternatively), a third charging unit U3 (a third diode D3 is connected with a third element R3 in series or alternatively), and a second capacitor C2, the mechanical switch K is closed, a first power supply provided by power supplies connected with two ends of the load RL charges the first capacitor C1 through the first charging unit U1, namely the series circuit formed by the first capacitor C1 and the first element R1 is connected with the load RL in parallel; the first power supply charges the second capacitor C2 through the second charging unit U2; the first capacitor C1, the third charging unit U3 and the second capacitor C2 form a tenth series circuit, and the first power supply charges the first capacitor C1 and the second capacitor C2 through the tenth series circuit.

In the breaking process of the mechanical switch K, a second power supply provided by a second capacitor C2 supplies power to a load RL through a first switch S1 and a first capacitor C1 (a second series circuit is formed by the first switch S1 and the first capacitor C1), so that the aim of arc extinguishing of the mechanical switch K is fulfilled, namely the voltage of the second capacitor C2 is superposed with the voltage of the first capacitor C1;

the capacity of the first capacitor C1 (an electrolytic capacitor can be adopted) is greater than that of the second capacitor C2 (the capacity of the first capacitor C1 is greater than twice that of the second capacitor C2), and the first capacitor C1 is connected in parallel with the first voltage-stabilizing device Z1 or a resistor for limiting the charging voltage of the first capacitor C1; the first diode D1 is connected in parallel with the second capacitor C2; the first capacitor C1 is connected in parallel with a fourth diode D4; the charge of the first capacitor C1 is larger than that of the second capacitor C2, and after the second capacitor C2 is discharged, the first capacitor C1 is discharged through the load RL, the first diode D1 and the first switch S1;

if the second capacitor C2 (an electrolytic capacitor may be used) is designed to have a capacity larger than that of the first capacitor C1 (the capacity of the second capacitor C2 is twice larger than that of the first capacitor C1), the charge of the second capacitor C2 is larger than that of the first capacitor C1, after the first capacitor C1 is discharged, the second capacitor C2 is discharged through the first switch S1, the fourth diode D4 and the load RL, and the first zener device Z1 is connected in parallel with the second capacitor C2 instead.

First switch S1: a voltage detection switch for detecting the potential difference or the voltage change rate between the first capacitor C1 and the second capacitor C2, or for detecting the voltage drop rate across the load RL; the power supply is provided by the voltage between the first capacitor C1 and the second capacitor C2 or is provided by the voltage non-isolation between the two ends of the load RL; the voltage input end and the output end of the voltage detection switch are not electrically isolated, and the first switch S1 is divided into a detection potential difference type or a detection voltage change rate type:

the first switch S1 shown in fig. 11 is a potential difference detection type, and is configured to detect a potential difference between the first capacitor C1 and the second capacitor C2, where the first switch S1 is composed of a fifth diode D5, a second voltage regulator Z2, and a first half-controlled device SCR1, the second capacitor C2 triggers the first half-controlled device SCR1 to turn on through the second voltage regulator Z2 (the voltage regulation value of the second voltage regulator Z2 needs to be greater than the peak value of the ripple voltage), the fifth diode D5 triggers the first half-controlled device SCR1 to turn on, and the second capacitor C2, the first half-controlled device SCR1, and the first capacitor C1 constitute a power supply circuit for supplying power to the load RL, and is configured to perform arc extinction and disconnection on the mechanical switch K.

As shown in fig. 12, the first switch S1 detects a voltage change rate type, the first switch S1 includes a third capacitor C3 and a first half-controlled device SCR1, the third capacitor C3 inputs a voltage signal, and the first switch S1 is used to detect a voltage change rate between the first capacitor C1 and the second capacitor C2; when the third capacitor C3 is instead connected to the ground of the load RL, the first switch S1 is used for the rate of change of the voltage across the load RL;

as shown in fig. 13, the first switch S1 detects a voltage change rate type, the first switch S1 is composed of a third capacitor C3, a first half-controlled device SCR1 and a delay unit B, the third capacitor C3 inputs a voltage signal, and the first switch S1 is used for detecting a voltage change rate between the first capacitor C1 and the second capacitor C2; when the fourth terminal of the delay unit B is connected to the common terminal of the mechanical switch K and the load RL, the first switch S1 is used to detect the voltage change rate between the common terminal of the mechanical switch K and the load RL and the second capacitor C2; when the third capacitor C3 is connected to the ground of the load RL instead, the first switch S1 is used to detect the voltage change rate across the load RL (the voltage across the load RL triggers the first half-controlled device SCR1 to turn on through the third capacitor C3);

a delay unit B: the specific circuit may be a circuit as shown in fig. 14, which comprises a power supply circuit (fourth element R4, third voltage regulator Z3), a delay circuit (fifth element R5, sixth element R6, fourth capacitor C4, first transistor Q1, fourth voltage regulator Z4, and a first stage current amplifier circuit may be added as required at the output end of first transistor Q1), a half-controlled switch circuit (seventh diode D7, second half-controlled switch SCR2, and seventh element R7), the operating power supply provided by second capacitor C2 is limited by fourth element R4, the third voltage regulator Z3 is used to stabilize and provide operating energy for the delay circuit, during the breaking process of mechanical switch K, at the moment of breaking of mechanical contact, the voltage drop rate at two ends of load RL is very high, the current provided by third capacitor C3 is enough to drive second half-controlled switch 2 to conduct, the second half-controlled switch SCR2 is used to drive the delay circuit to conduct the delay device 1, the purpose of arc extinction of the mechanical switch K is achieved.

The second half-controlled switch SCR2 may be a unidirectional thyristor, and in order to save cost and facilitate adjustment of electrical parameters, it is proposed to replace the second half-controlled switch SCR2 with a thyristor equivalent circuit, as shown in fig. 15, which is formed by two transistors, and is further connected in parallel with a fifth voltage regulator Z5.

In this embodiment, the third capacitor C3 is proposed to be connected in series with a parallel circuit (as shown in fig. 16) composed of a resistor R10 (tenth element) and a diode D8 (eighth diode), which can overcome the impact current generated by the closing of the mechanical switch K and does not affect the accuracy of the first switch S1 in detecting the voltage change rate.

When the first switch S1 is a voltage change rate detection type switch, it is particularly suitable for use in situations where voltage fluctuation or ripple is large, such as in a battery power supply system of an electric vehicle or an ac rectification power supply system.

This embodiment, for two end circuit, has the circuit simply, the reliability is high, convenient to use's advantage.

Fig. 17 shows an arc extinguishing device according to a seventh embodiment of the present invention:

in order to facilitate use and popularization, the sixth embodiment of the arc extinguishing device is packaged into a device by adopting an insulating material, and the device is used as a product with strong universality, is convenient for safety certification, and can be flexibly designed according to the specific appearance.

In the above embodiment, the capacitance of the first capacitor C1 is preferably selected such that the on time of the first switch S1 is not more than 1 millisecond (preferably within 200 microseconds, as long as a pulse current of several tens of microseconds is applied to the load to achieve a satisfactory arc extinguishing effect).

The first power supply to charge the first capacitor C1 in the above embodiment is provided by the power supply of the first series circuit connection in non-isolated, i.e. non-electromagnetically isolated.

The above fully-controlled switch is preferably a fully-controlled semiconductor device (semiconductor switch), such as a triode, a field effect transistor, an IGBT and other types of devices (a diode can be arranged inside);

the above half-controlled switch is preferably a half-controlled semiconductor device (semiconductor switch), such as a one-way thyristor or the like.

In the above embodiment, the first switch S1 or the fourth switch S4 is preferably connected in series with at least one diode to prevent the sudden occurrence of reverse voltage (e.g., the mechanical switch K bounces) in the on state from damaging the first switch S1 or the fourth switch S4.

In the above embodiment, the first capacitor C1 may be connected in series with an inductive current limiter (which may be omitted when the internal resistance of the first capacitor C1 to the working circuit of the load RL is large) for increasing the power supply time of the first capacitor C1 to the load RL and reducing the rising rate of the current; selecting parameters of the series inductance: under the actual working condition, the current rising rate of the device passing through the first switch S1 is smaller than the limit rising rate of the first switch S1; in order to achieve the best efficiency and safety, a lead can be used for short-circuiting the two ends of the load RL on site; or a capacitor (or other capacitive or resistive load) is used for connecting two ends of the load RL in parallel; the first capacitor C1 charges and then the first switch S1 turns on, and the second power is superimposed with the voltage of the first capacitor C1 so that the current rise rate through the first switch S1 is less than the limit rise rate of the first switch S1.

In summary, the above embodiments of the present invention have the following advantages:

1. the capacity utilization rate of the capacitor is high, the charging speed of the capacitor is high, the charging voltage of the capacitor can be adjusted, and the influence on the overvoltage of a system is reduced.

2. The voltage larger than the input power voltage of the mechanical switch can be provided for the load, and the arc extinguishing circuit can output extremely large arc extinguishing current (the square lead of 1 can transmit hundreds to thousands of amperes of current) under the conditions of long circuit, small wire diameter and large internal resistance of the arc extinguishing circuit.

3. The charging power supply of the capacitor is provided by the power supply non-isolated (electromagnetic isolation and transformer isolation) connected with the mechanical switch, the arc extinguishing voltage is improved without a transformer, the withstand voltage requirement of the capacitor is not required to be improved, and the charging power supply of the capacitor is simple in circuit, small in size, low in cost and high in reliability.

4. High response speed, large output current and good arc extinguishing effect.

Claims

The utility model provides an arc extinguishing circuit, the mechanical switch that needs the arc extinguishing constitutes first series circuit with load series connection, characterized by: the charging circuit comprises a first switch, a first charging unit and a first capacitor;

a first power supply charges the first capacitor through the first charging unit, and a second power supply supplies power to the load through the first switch and the first capacitor in the breaking process of the mechanical switch;

the first charging unit comprises a first element, or is a second switch, or consists of the first element and the second switch which are connected in series.
The arc quenching circuit of claim 1, wherein: the first power source is provided by a power source connected to the first series circuit.
The arc quenching circuit of claim 1, wherein: the first switch and the second switch are semiconductor switches.
The arc quenching circuit of claim 1, wherein: the second switch is used for adjusting the charging voltage of the first capacitor.
The arc quenching circuit of claim 1, wherein: the mechanical switch is connected in series with a one-way conduction device, and the one-way conduction device is connected in parallel with a bypass switch.
The arc quenching circuit of claim 1, wherein: the first capacitor is discharged through the first element and the second switch.
The arc quenching circuit of claim 1, wherein: the first power source is provided across the load and the second power source is provided by a power source connected across the first series circuit.
An arc quenching circuit according to any of claims 1 to 5, characterized in that: the first capacitor is connected with the first switch, the second capacitor is connected with the second switch, and the third switch, the first switch and the second switch form a third series circuit; the first switch, the first capacitor and the fourth switch form a second series circuit, and in the breaking process of the mechanical switch, the second power supply supplies power to the load through the second series circuit; the number of the mechanical switches, the load and the fourth switches is one, two or more.
The arc quenching circuit of claim 8, wherein: the first power supply and the second power supply are provided by power supplies connected to two ends of the first series circuit.
The arc quenching circuit of claim 8, wherein: and the third switch and the fourth switch form a fourth series circuit, before or in the closing process of the mechanical switch, the second power supply supplies power to the load through the fourth series circuit, and the third switch or the second element is connected in series.
The arc quenching circuit of claim 8, wherein: the first capacitor discharges the circuit through the first diode and the third switch; or the first capacitor is discharged through the second switch and the first diode.
The arc quenching circuit of claim 8, wherein: the third switch is a full-control switch or a semi-control switch; the fourth switch is a semi-controlled switch.
The arc quenching circuit of claim 8, wherein: the fourth switch is a semiconductor switch.
The arc quenching circuit of claim 13, wherein: the fourth switch is connected with at least one diode in series.
The arc quenching circuit according to any of claims 1 to 6, characterized in that: the power supply further comprises a second capacitor, and the second power supply is provided by the second capacitor.
The arc quenching circuit of claim 15, wherein: the first power source is provided by both ends of the load or by a power source connected across the first series circuit.
The arc quenching circuit of claim 15, wherein: the second charging unit is used for charging the second capacitor, and is a second element, or a seventh switch, or is formed by connecting the second element and the seventh switch in series.
The arc quenching circuit of claim 17, wherein: the first capacitor is connected with the first switch, the second capacitor is connected with the second switch, and the third switch, the first switch and the second switch form a third series circuit; the first power supply is used for charging the second capacitor through the third switch and the second charging unit, the first switch, the first capacitor and the fourth switch form a second series circuit, in the breaking process of the mechanical switch, the second power supply is used for supplying power to the load through the second series circuit, and the number of the mechanical switch, the load and the fourth switch is one, two or more.
The arc quenching circuit of claim 18, wherein: the third series circuit further comprises a second element through which the first power supply is connected to the third switch, the common terminal of the second element and the third switch being connected to a fourth capacitance.
The arc quenching circuit of claim 18, wherein: the third series circuit also comprises a third element, and the second switch is a non-control switch or a semi-control switch; the first power source charges the second capacitor through the third element, the third switch, the second element and the seventh switch; the first power source charges the first capacitor through the eighth series circuit; the seventh switch is a non-controllable switch or a controllable switch.
The arc quenching circuit of claim 20, wherein: the capacity of the second capacitor is larger than that of the first capacitor, and the second capacitor is connected with the first voltage stabilizing device in parallel; or the capacity of the first capacitor is larger than that of the second capacitor, and the first capacitor is connected with the first voltage stabilizing device in parallel.
The arc quenching circuit of claim 20, wherein: the first power supply charges the second capacitor through the third series circuit.
The arc quenching circuit of claim 20, wherein: the third series circuit further comprises a third element through which the first power source is connected to the third switch, and a common terminal of the third element and the third switch is connected to a fourth capacitor.
An arc extinguishing device comprising an arc extinguishing circuit according to any of claims 1 to 6, characterized in that: the control unit is used for providing control signals of the first switch and the second switch.
The arc extinguishing device of claim 24, wherein: the control unit is used for detecting the charging voltage of the first capacitor.
The arc extinguishing device of claim 24, wherein: and voltage signals at two ends of the mechanical switch are transmitted to the control unit, or signals of an auxiliary switch of the mechanical switch are transmitted to the control unit.
An arc extinguishing device according to claim 24, characterized in that: it is placed in a housing and connected to the mechanical switch through terminals.
An arc extinguishing device including the arc extinguishing circuit of any one of claim 8, characterized in that: the control unit is used for providing control signals of the first switch, the second switch and the third switch; the control signal of the fourth switch is provided by the control unit, or the control electrode of the fourth switch is connected with the load ground through a capacitor, or the control electrode of the fourth switch is connected with the input end of the mechanical switch through a capacitor.
An arc extinguishing device according to claim 28, wherein: and the voltage signal of the first capacitor is transmitted to the control unit.
An arc extinguishing device according to claim 28, wherein: and a voltage signal of a power supply at the input end of the mechanical switch is connected to the control unit.
An arc extinguishing device according to claim 28, wherein: and a voltage signal of a common end of the mechanical switch and the load is transmitted to the control unit.
An arc extinguishing device according to claim 28, wherein: the control signal of the mechanical switch is transmitted to the control unit, or the control unit provides the control signal of the mechanical switch, or the auxiliary switch signal of the mechanical switch is transmitted to the control unit.
An arc extinguishing device according to claim 28, wherein: the control unit adjusts the charging voltage of the first capacitor according to the current passing through the mechanical switch.
An arc extinguishing device according to claim 28, wherein: the control unit is used for controlling the first switch to be switched on and off, and the first switch, the second switch and the third capacitor are connected in series; and the sixth switch, the third capacitor and the fourth switch form a sixth series circuit, in the breaking process of the mechanical switch, the second power supply supplies power to the load through the sixth series circuit, and the fifth switch is a diode or a controllable switch provided by the control unit for a control signal.
An arc extinguishing device according to claim 28, wherein: the power supply of the input end of the mechanical switch is connected with the common end of the eighth switch and the fourth switch through the sixth element, and a voltage signal of the common end is transmitted to the control unit.
An arc extinguishing device according to claim 28, wherein: it is placed in a housing and connected to the mechanical switch through terminals.
An arc extinguishing device including the arc extinguishing circuit of any one of claim 18, characterized in that: the control unit is used for providing control signals of the first switch, the second switch and the third switch; the control signal of the fourth switch is provided by the control unit, or the control electrode of the fourth switch is connected with the load ground through a capacitor, or the control electrode of the fourth switch is connected with the input end of the mechanical switch through a capacitor, and the number of the mechanical switch, the load and the fourth switch is one, two or more.
An arc extinguishing device according to claim 37, characterized in that: and the voltage signal of the first capacitor is transmitted to the control unit.
An arc extinguishing device according to claim 37, characterized in that: and a voltage signal of a power supply at the input end of the mechanical switch is connected to the control unit.
An arc extinguishing device according to claim 37, characterized in that: and a voltage signal of a common end of the mechanical switch and the load is transmitted to the control unit.
An arc extinguishing device according to claim 37, characterized in that: the control signal of the mechanical switch is transmitted to the control unit, or the control unit provides the control signal of the mechanical switch, or the auxiliary switch signal of the mechanical switch is transmitted to the control unit.
An arc extinguishing device according to claim 37, characterized in that: the control unit adjusts the charging voltage of the first capacitor according to the current passing through the mechanical switch.
An arc extinguishing device according to claim 37, characterized in that: the power supply of the input end of the mechanical switch is connected with the common end of the eighth switch and the fourth switch through the sixth element, and a voltage signal of the common end is transmitted to the control unit.
An arc extinguishing device according to claim 37, characterized in that: the switch circuit further comprises a ninth switch, a series circuit formed by the first capacitor and the ninth switch is connected with the fourth switch, and a voltage signal at the common end of the series circuit and the fourth switch is transmitted to the control unit.
An arc extinguishing device according to claim 37, characterized in that: it is placed in a housing and connected to the mechanical switch through terminals.
An arc quenching device including the arc quenching circuit of claim 15, characterized in that: the first power supply is provided by two ends of the load, the first power supply further comprises a second charging unit, the first power supply is used for charging the first capacitor through the first element, the first power supply is used for charging the second capacitor through the second charging unit, the first capacitor is connected with a voltage stabilizing device or a resistor in parallel, the first switch is a voltage detection switch, and the voltage detection switch is used for detecting the potential difference or the voltage change rate between the first capacitor and the second capacitor or is used for detecting the voltage reduction rate at two ends of the load.
An arc extinguishing device according to claim 46, wherein: the first capacitor, the second charging unit and the second capacitor form a tenth series circuit, and the first power supply charges the first capacitor and the second capacitor through the tenth series circuit.
An arc extinguishing device according to claim 46, wherein: the first capacitor, the third charging unit and the second capacitor form a tenth series circuit, and the first power supply charges the first capacitor and the second capacitor through the tenth series circuit; the third charging unit is formed by connecting a third diode and a third element in series; or a third element; or a third diode.
An arc extinguishing device according to claim 46, wherein: the third charging unit is formed by connecting a second diode and a second element in series; or a second element; or a second diode.
An arc extinguishing device according to claim 46, wherein: the capacity of the first capacitor is larger than that of the second capacitor, and the first capacitor is connected with the first voltage stabilizing device in parallel; or the capacity of the second capacitor is larger than that of the first capacitor, and the second capacitor is connected with the first voltage stabilizing device in parallel.
An arc extinguishing device according to claim 46, wherein: the first switch is composed of a fifth diode, a second voltage stabilizing device and a first semi-controlled device, and the second capacitor triggers the first semi-controlled device to be conducted through the second voltage stabilizing device and the fifth diode.
An arc extinguishing device according to claim 46, wherein: the first switch comprises a third capacitor, and the third capacitor is used for inputting a voltage signal.
An arc extinguishing device according to claim 52, wherein: the first switch consists of the third capacitor and a first semi-control device; the second capacitor triggers the first semi-controlled device to be conducted through the third capacitor, or the voltage of the load triggers the first semi-controlled device to be conducted through the third capacitor.
An arc extinguishing device according to claim 52, wherein: the first switch is composed of the third capacitor, a first semi-controlled device and a delay unit, the voltage signal is transmitted to the delay unit through the third capacitor, and the delay unit drives the first semi-controlled device to be conducted.
An arc extinguishing device according to claim 54, wherein: the delay unit is composed of a power supply circuit, a delay circuit and a semi-controlled switch circuit, the power supply circuit is composed of a fourth element and a third voltage stabilizing device, a working power supply provided by the second capacitor is limited in current through the fourth element, and the third voltage stabilizing device stabilizes voltage to provide working energy for the delay circuit.
An arc extinguishing device according to claim 46, wherein: the power supply of the voltage detection switch is provided by the voltage between the first capacitor and the second capacitor, or is provided by the voltage across the load in a non-isolated mode.
An arc extinguishing device according to claim 46, wherein: and the voltage input end and the output end of the voltage detection switch are not electrically isolated.
An arc extinguishing device according to claim 46, wherein: which is encapsulated as a device using an insulating material.
An arc extinguishing device according to any one of claims 24, 28, 37 and 46, wherein: the control unit also includes a communication port.